Boat stabilizing units



March 12, 1968 L. LO BUE BOAT STABILIZING UNITS 2 Sheets-Sheet 1 FiledOct. 5, 1966 ATTORNEYS.

March 12, 1968 U 3,372,663

BOAT STABILIZING UNITS Filed Oct 5, 1966 2 Sheets-$heet 2 r INVENTOR. 54 [5 LOU/5 LoBl/E ATTORNEYS.

United States Patent Office 3,372,663 Patented Mar. 12, 1%68 3,372,663BOAT STABILIZING UNITS Louis L Bue, Paterson, N.J., nssignor to AquaStables, Inc., Paterson, NJ., a corporation of New Jersey Filed Oct. 5,1966, Ser. No. 584,416 13 Claims. (Cl. 114-665) The present inventionrelates to boat stabilizing units and more particularly to trim tabattachments for the transom tor hull of a power driven boat.

The forward motion of a power boat, whether of the inboard or outboardvariety, generally results in the lifting of the forward section or thebow out of the water. The same lifting effect may be similarly caused byturbulent water. This lifting of the bow results in drag due to Waterresistance, a choppy ride and additionally may block the vision of theboat operator due to the angle of elevation of the how.

The lifting in many instances causes substantial loss in efficiency ofthe power motor, not only due to the extra drag caused by waterresistance, but due to the fact the uneveness or chopping effect of thecraft in the water many times is so severe that it can raise thepropellor out of the water for short intervals.

In the past, numerous devices have been employed in an attempt tostabilize the craft in a fairly horizontal plane with respect to thewater and generally these devices were in the form of mechanicallyactuated or controlled elevator plates aflixed to the stern or transomof the craft at approximately water level. These plates were in mostcases permanently aflixed directly to the transom so as to angledownward into the water to create a lifting force at the rear of thecraft during forward movement of the craft.

Since the lifting force at the rear of the craft was a function of theforward speed of the c aft and the angle of the plates, these fixedplates were generally inefiicient and had to be pre-set for a singleneed.

Other devices were developed to allow for the change in the angle of theplates by mechanical means such as by electrical controls, fluidpressure, etc., however, since these devices had to be actuated by thecraft operator, and ac tuation of these devices was desirable at thesame time a change in speed was desired, it became a complicatedmaneuver for the operator. Additionally, the mechanical adjustment meanswere both comparatively expensive and were dependent upon auxiliarypower sources which could fail.

Simpler devices were developed such as through the user of compressionsprings which were aflixed to the plates and depending upon theadjustment of, and the compressional strength of the springs, reset theangle of the plates for differing speeds. However, even these deviceswere dependent upon mechanical aids for actuation, and were generallypre set, at least in normal position so that the plates were angu'latedat a relatively high pitch for low speeds and light loads. It was alsodifficult to readily adapt such devices which were normally used inpairs to compensate for any natural roll or list which a craft mighthave due to its construction or the lack of balance of the load in thecraft.

The trim tab of the present invention is a self'actuating,self-adjusting device mounted so as to be slightly below the waterlevel, affixed to the transom of the craft, with the tab pivotallymounted at a point outward of the transom, along its length so as topivot from a horizontal plane to a pitched angle by the action of thewater itself, the pitch being a direct function of the speed of thecraft, thereby eliminating the requirement of mechanical adjustment byeither the operator or through other means. By selective setting of thepivot points, a wide variety of selective angulation of the craft tomeet varying needs is provided.

Although such novel feature or features believed to be characteristic ofthe invention are pointed out in the claims, the invention and themanner in which it may be carried out may be further understood byreference to the decsription following and the accompanying drawings.

FIG. 1 is a perspective view of the trim tabs of the present inventionaflixed to the transom of a craft.

FIG. 2 is a plan view of a craft employing the trim tabs showing thecraft during the initial period of forward motion.

FIG. 3 is a plan view of the craft of FIG. 2 with the trim tabsactuated.

FIG. 4- is a section of FIG. 1 along lines 4-4, showing the device inoperative position.

FIG. 5 is a partial section of FIG. 4 along lines 55.

FIG. 6 is an another embodiment of FIG. 5.

FIG. 7 is a perspective view of another embodiment of the presentinvention.

Referring now to the figures in greater detail, Where like referencenumber denote like parts in the various figures.

As shown in FIG. 1, the trim tab 1 of the present invention is generallyemployed in pairs affixed to the transom 2 or stern of a craft 3. Asmore particularly shown in FIG. 4, the trim tab 1 comprises astabilizing tab 4 of a substantially fiat rectangular configurationhaving upwardly flanged sides 5 and as shown in FIG. 4, an upward rearflange 6. A spine 26 may be formed along one edge of the stabilizing tab4 for rigidity.

A series of registered openings 7 are provided along the flanged sides 5and provide varied pivot points for the stabilizing tab 4.

As shown in FIGS. 1 and 4, stabilizing tab 4 is pivotally mounted at apoint outward of the transom 2 within tab housing 8, through side plates9, the housing 8 having a substantially hollow bottom, withsubstantially L- shaped side plates 9, back plate 10, and sloping roof11.

In lieu of tab housing 8, as shown in FIG. 7, side plates 12 of the samegeneral configuration and structure of side plates 9 can be employed,wherein side plates 12 are provided with a right angle flanged portion13 able to function as back plate 10.

A series of openings 14 arcuately aligned, may be provided along theraised leg portion side plates 9, and are so positioned that upon thepivoting of stabilizing tab 4 within tab housing 8, a portion of flangedsides 5 of stabilizing tab 4 will intersect with openings 14. A seriesof openings 16 along the bottom leg of side plate 9 may also be providedin parallel plane to openings 7 on stabilizing tab 4.

Tab housing 8 is affixed to transom 2 by ordinary means such as byscrews 15 through back plate 10, or as as shown in FIG. 7, throughflanges 13. It has been found that screws are preferable for s0 affixingsince it is not necessary to provide a thorough opening in transom 2 insuch case, thereby avoiding the necessity of providing water sealingapparatus. However, nuts and bolts with seal Washers are useable.

The pivotal mounting of stabilizing tab 4 to side plates 9 or 12 iseffected by the insertion of a pivoting member through a preselectedopening 16 and a preselected opening 7 of trim tab 4 and securing asshown in FIG. 5. A bolt 17 is employed in combination with a washer 18and a lock nut arrangement 19. A bushing 20 can be provided between sideplate 9 and flanged side 5, or a washer arrangement 21 such as shown inFIG. 6 will suflice. The bolt 17 combination will be in constant contactwith the water and it should be rust resistant and the bushing 20 ispreferably of plastic. The bushing 26 may be flanged or tightly set soit will not fall out of place while the tab 4 is being set and alsoreduces friction.

To aid in assembly and to make interchange of pivot points easier, inlieu of bolt 17, as shown in FIG. 7, a rod 22 can be provided pivotallyinterconnecting side plates 12 with trim tab 4 through side flanges 5.

The maximum desired pivot of stabilizing tab 4 can be selectivelycontrolled by the insertion of a stop 23 which can be a simple nut andbolt or plug arrangement within preselected opening or openings 14 onside plates 8.

As shown in FIG. 4, the back plate 10 of housing 8 can be L shaped so asto extend below and beneath the rear flange 6 of stabilizing tab 4.While there is preferably no abutment of the stabilizing tab 4 with thevertical portion of back plate 10, the lip of the L of back plate 10acts as a stop against undesired reversal of angle of stabilizing tab 4.

As shown in FIG. 7, in lieu of the L-shaped flange on back plate 10,where no back plate 10 is employed, an L-shaped stop bracket 24 can beemployed, functioning in the same manner as flange 25.

Where it is desired to provide a minimum angle of elevation forstabilizing tab 4, stop bracket 24 can be affixed to the transom 2 in aslightly elevated position with respect to the normal horizontal planeof stabilizing tab 4. The same result can similarly be accomplished byhaving the bottom leg of L-shaped flange 25 bent at an upward angle.

In lieu of stop 23 on side plates 9, the roof 11 may act as a stopagainst rotation of stabilizing tab 4. Where stop 23 is employed, roof11 is unnecessary; however, it is preferably included since it not onlyadds stability to the housing 8 or side plate arrangement as shown inFIG. 7, it additionally acts as a splash guard and may give somepropulsive force jetting out a water stream while the boat is in motion.

In operation, the trim tab 1 is aflixed to the transom 2 either throughback plate 10 or flanges 13 so that the trim tab 1 would be slightlybelow the water level of the craft when the craft is in a generallyhorizontal position. The stabilizing tab 4 is pivotally aflixedpreferably having a greater surface area inboard of the pivot pointsalthough such positioning is not critical.

As shown in FIG. 2, when the craft 3 begins its forward movement, thebow will be slightly elevated. As the craft travels through the water asshown in FIG. 3, water pressure beneath the craft will pivot stabilizingtab 4 upward at its inboard portion. Angulation of the stabilizing tab 4is a function of the water pressure and the natural planing of the craft3 on the water. During slower speeds or rough weather, the angle ofelevation of the stabilizing tabs 4 will be greatest, the stabilizingtabs 4 raising the stern and keeping the craft 3 in a horizontal plane.As the speed of the craft 3 increases, the stabilizing tabs 4 willsimilarly maintain the craft 3 in horizontal position. However, theangle of elevation will lessen the efiect being similar to the efiect oftrim tabs of an air foil. By selection of pivot points and stops 23, thepresent invention is readily adaptable for use with varying crafts,varying engines on the same craft or for varying the desired plane ofdrive for a craft. The tab 4 has a wide range of adaptation to both loadand speed once the pivot point is selectedand stops set. It is alsoadaptable when used in pairs for compensating for a natural roll or listof a craft due to construction by varying the pivot points on each ofthe two trim tabs 1.

While as shown in the drawing, the trim tab 1 of the present inventionis shown affixed to the stern or transom 2 of the craft 3, it ispossible to affix the trim tabs 1 on either side of the craft 3.

The terms and expressions which are employed are used as terms ofdescription; it is recognized, though, that various modifications arepossible within the scope of the invention claimed.

Having thus described certain forms of the invention in some detail,what is claimed is:

1. A self adjusting trim tab adapted to be mounted on a water craftcomprising, one portion adapted to be mounted on said craft, astabilizing tab, a first stabilizing tab mounting means, a secondstabilizing tab mounting means, said first and second stabilizing tabmounting means extending longitudinally with respect to said craft, alower stabilizing tab stop, an upper stabilizing tab stop, means.iaintaining said first and second stabilizing tab mounting means infixed relationship, and pivot means intermediate the length of saidstabilizing tab mounting means adapted to allow said stabilizing tab topivot between said lower and upper stops.

2. The invention of claim 1 wherein said first and second stabilizingtab mounting means are substantially L-shaped.

3. The invention of claim 1 wherein said pivot means include a pair ofupwardly extending side flanges extending from said stabilizing tab,each said side flange having at least one opening therethrough, at leastone opening on each of said first and second stabilizing tab mountingmeans in registration with said side flange opening and fixed meanspassing through said registered openings whereby said stabilizing tabmay rotate about said fixed means.

4. The invention of claim 3 wherein said fixed means pass through aflanged bushing, said bushing flange interposed between said stabilizingtab and said stabilizing tab mounting means.

5. The invention of claim 1 wherein said pivot means comprise a rodmember extending through said side flanges and said stabilizing tabmounting means.

6. The invention of claim 3 wherein each said side flange and each saidfirst and second stabilizing tab mounting means includes a plurality ofopenings providing selective pivot points for said stabilizing tab.

7. The invention of claim 1 wherein said upper stabilizing tab stopmeans comprise at least one opening on said stabilizing tab mountingmeans, said opening along an intersecting plane with said stabilizingtab when said stabilizing tab is pivoted upward, and fixed means withinsaid opening projecting inward between said first and second stabilizingtab mounting means.

8. The invention of claim 7 including a plurality of openings along saidintersecting plane with said stabilizing tab when said stabilizing tabis pivoted upward for selective positioning of said fixed means.

9. The invention of claim 1 wherein said lower stabilizing tab stopmeans includes afixed member below one edge of said stabilizing tab.

10. The invention of claim 1 wherein a roof member is provided abovesaid first and second stabilizing tab mounting means integral to firstand second stabilizing tab mounting means.

11. The invention as claimed in claim 10 wherein a back plate isprovided integral 'to said first and'second stabilizing tab mountingmeans and said roof member to form a housing for said stabilizingvtab.

12. The invention as claimed in claim 1 wherein said stabilizing tabincludes a spine.

13. In combination with a water craft, a pair of self adjusting trimtabs, each said trim tab including one portion adapted to be mounted onsaid craft, a stabilizing tab, a first stabilizing tab mounting means, asecond stabilizing tab mounting means, said first and second stabilizingtab mounting means extending longitudinally 6 with respect to saidcraft, a lower stabilizing tab stop, References Cited an upperstabilizing tab stop, means maintaining said first and secondstabilizing tab mounting means in fixed UNITED STATES PATENTSrelationship, and pivot means intermediate the length 1,003,364 9/1911Langston 114-665 of said stabilizing tab mounting means adapted to allow5 3,200,782 8/1965 Walden et :al. 114-66,.5 said stabilizing tab topivot between said lower and up- 3,326,164 6/1967 Kercheval 114-66.5

per stops, each said trim tab mounted in fixed position below the waterlevel of said craft in spaced apart re- ANDREW H. FARRELL, PrimaryExaminer. lationship.

1. A SELF ADJUSTING TRIM TAB ADAPTED TO BE MOUNTED ON A WATER CRAFTCOMPRISING, ONE PORTION ADAPTED TO BE MOUNTED ON SAID CRAFT, ASTABILIZING TAB, A FIRST STABILIZING TAB MOUNTING MEANS, A SECONDSTABILIZING TAB MOUNTING MEANS, SAID FIRST AND SECOND STABILIZING TABMOUNTING MEANS EXTENDING LONGITUDINALLY WITH RESPECT TO SAID CRAFT, ALOWER STABILIZING TAB STOP, AN UPPER STABILIZING TAB STOP, MEANSMAINTAINING SAID FIRST AND SECOND STABILIZING STOP, MOUNTING MEANS INFIXED RELATIONSHIP, AND PIVOT MEANS INTERMEDIATE THE LENGTH OF SAIDSTABILIZING TAB MOUNTING MEANS ADAPTED TO ALLOW SAID STABILIZING TAB TOPIVOT BETWEEN SAID LOWER AND UPPER STOPS.